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arXiv · hep-th/0611193

S-duality in String Gas Cosmology

S. Arapoglu·A. Karakci·A. Kaya
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Abstract

We consider a toy cosmological model in string theory involving the winding and momentum modes of (m,n) strings, i.e. bound states of m fundamental and n D-strings. The model is invariant under S-duality provided that m and n are interchanged. The dilaton is naturally stabilized due to S-duality invariance, which offers a new mechanism of moduli fixing in string gas cosmology. Using a tachyon field rolling down to its ground state, we also point out a possible way of realizing a cosmological phase with decreasing Hubble radius and constant dilaton.

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S. Arapoglu, A. Karakci, A. Kaya. 2006-11-27. S-duality in String Gas Cosmology. https://doi.org/10.1016/j.physletb.2006.12.051

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